Before the first message, select an API model or an authorized connection. Existing chats keep their engine; a CLI chat can change models within its connection. In DeepAgents, type an at sign to select a workspace file, and attach images with the attachment button. CLI chats also accept files, with different picker behavior. DeepAgents offers Web, Image, Speech, and Video controls. Plan Mode asks it to plan first. Each capability still needs the corresponding model and credentials. Enter sends; Shift-Enter adds a line. Click the microphone to start and again to finish; recognized speech is sent. During a run, text follow-ups can queue. Read approval details before allowing or rejecting an operation. Stop requests cancellation without undoing completed actions. DeepAgents interrupt-and-send also waits for the stop to be acknowledged. DeepAgents automatic locks coordinate available regions. Manual mode locks selected files or folders and leaves others read-only. Agent-selected mode declares a region when writing is needed. The header opens service testing, Tracing, active processes, and files. Active processes shows locked paths. Force release removes a lock; it does not stop the agent. Practice referencing a file and asking for a summary before an edit. Check the output and path. Start a new chat to change engines, and inspect lock conflicts.